1. Field of the Invention
The invention relates generally to cervical specimen collecting devices and more particularly to a cytological specimen scraper or spatula.
2. Brief Description of the Prior Art
Cytological specimen samplers have been employed to obtain cervical-vaginal specimens by scraping the cervical region with a bladed spatula. Among the commonly used samplers was the cervical scraper described in U.S. Pat. No. 2,471,088, issued to Dr. James Ernest Ayre. This scraper was designed with a heart shaped tip comprised of a pair of divergent peaks, both offset from the axis of a stem in opposite directions. In use, one of the peaks was positioned against the cervical orifice, and the scraper was rotated while held in such position allowing the other peak to lightly scrape the circumference of the cervical lip.
A substantial number of cytological specimens obtained with scrapers such as the Ayre scraper did not indicate cells of endocervical origin and a swab was often conjunctively employed to obtain an endocervical sampling. Utilization of the scraper-swab technique, however, still did not achieve adequate endocervical samplings and an average of 50% of the specimens examined at processing laboratories did not contain endocervical cells. This fact is of major significance because it has been determined that a majority of early cervical carcinomas begin in the canal above the upper limits of the squamous epithelium and for this reason a satisfactory specimen for cytological analysis must contain cells of endocervical origin.
Studies have revealed that the area of transition or transition zone between the histologic portio and the endocervix provides endocervical cells and is therefore of particular pathological importance. Thus, the transition zone has become the target area for obtaining an adequate cytological specimen.
The broad pivotal tip of the Ayre spatula did not function to permit adequate penetration into the transition zone due to both its relatively short length and its broad span. Furthermore, manipulation of the spatula itself was awkward since the stem or rotating axis was offset with respect to the pivotal tip. When attempts were made to rotate the spatula about a fixed axis of rotation, the offset tip generated a broad circular path displacing the cervix and often produced hemorrhaging and trauma.
Returning to the recognition of the transition zone as the target area for specimen samplings, it has been determined that the zone varies in length and position and generally ascends the canal as the patient's age increases. This presented even further difficulties with respect to the use of the Ayre spatula because penetration of its broad tip was hampered due to the decreased elasticity of atrophic cervixes.
After some of the foregoing problems were appreciated attempts were made at providing modified scraper designs which would permit penetration deeper into the canal. An example of such attempts was illustrated in U.S. Pat. No. 3,352,299 wherein an elongate slender semi-eliptical scraper tip was designed for insertion into the canal. The use of scrapers of such configuration has not been widespread due to the increased incidence of hemorrhaging associated with the relatively pointed tip and the trauma inherent with deep penetration particularly when sharp implements were employed. Further, when such implement was inserted and inward pressure exerted against the face of the cervical portio, deflection of the cervix became a significant problem and adequate specimens could not be obtained without the exercise of a high degree of skill.
A further problem with regard to such scrapers was that since the protuberance was slender and long the scraper could not be fabricated of wood without the danger of possible tip fracture during manipulation within the canal and such scrapers were therefore restricted to plastics which resulted in higher costs and presented a sampling surface to which specimens did not readily adhere.